Instrument for solving triangles



5 Sheets-Sheet l June 29, 1937. E. c. LYONS ET AL INSTRUMENT FOR SOLVINGTRIANGLES Filed Nov. 15, 1934 I 7.3 52 5/ 1' mli! O 72 L55 5? mvz/avTURS -c. wows EV W )47-7-UF A/E/ 7 June 29, 1937. E, c LYGNS ET AL2,085,375

INSTRUMENT FOR SOLVING TRIANGLES Filed Nov. 15, 1934 3 Sheets-Sheet 2.

y mmi )4 TTU A/E June29, 1937. E. c. LYONS ET AL INSTRUMENT FOR SOLVINGTRIANGLE ES Filed Nov. 13, 1934 3 Sheets-$heet 3 Q55 7. fig 5.

Patented June 2%, 1&3?

STTES PATENT E FHCE Ellis 0. Lyons and Raymond G. McMahon, Portland,Oreg.

Application November 13, 1934, Serial No. 752,808

Claims.

This invention relates generally to the solution of triangles, andparticularly to an instrument by means of which triangles may be solvedmechanically.

The main object of this invention is the provision of an instrument fora special use in connection with the control of artillery fire by meansof which the range in units of distance such as yards or meters from thegun position to the target, as well as the firing angle in mills or theunits of angular measurement may be quickly and accurately determinedwithout the use of mathematics.

This object is accomplished in the manner set forth in the specificationfollowing and illustrated in the accompanying drawings, in which:

Fig. l is an extended vertical section taken along the line il in Fig.2.

Fig. 2 is a plan of the device showing a representative setting of theinstrument arms.

Fig. 3 is a diagrammatic plan showing a practical application of theinstrument in a fire control problem.

Fig. 4 is a section taken along the line 4-4 in Fig. 1.

Fig. 5 is a plan of an upper arm and its Vernier.

Fig. 6 is a fragmentary plan view of the azimuth scale.

Fig. 7 is a section taken along the line 1-7 in Fig. 1.

Fig. 8 is a section taken along the line 8-8 in Fig. 1.

Fig. 9 is a plan of a portion of the arm shown in Fig. 8.

Fig. 10 is a horizontal section along the line lill!l in Fig. 1.

Similar numbers of reference refer to similar parts throughout theseveral views.

For the purpose of explaining the operation of this device in itssimplest form, which is also adaptable for portable use, for example infield artillery operations, there is shown a tripod comprising the legsii and the head IE to which the legs are secured by means of the boltsI3. Rotatably mounted in the head 52 is the vertical spindle 4 which maybe clamped in a fixed position within the head i2 by means of the wedgepin which reacts against the wedge sleeve [6 under the action of a thumbnut ll on the threaded end l'l-A of the pin i5. Obviously, any otherform of clamp which is suitable for the purpose may be employed withoutdeparting from the spirit of this invention.

Mounted on the spindle l4 and integral therewith is a circular housingE8 in Whose upturned sides 19 is secured a base plate 20 by means of thescrews 2 I. Extending through the base plate 20 and journaling in theanti-friction bearings 22 is the main spindle 23 on whose lower end issecured a worm wheel 24 which meshes with a worm 25 whose shaft 26journals in the hinged arm 21, one end of which is carried by the pin 28and the other end of which is urged toward a stop 29 by means of aspring 30. Rotation is supplied to the shaft 26 by means of a knurledhead 3! The parts 28-3l are not illustrated but are duplicates of parts39 to 42 shown in Fig. 'i.

The worm wheel 24 bears against the under side of the base plate 25. Onthe top side of the base plate 20 is mounted a worm wheel 32 whose hub33 is rotatable on the sleeve 33 which extends into and is locked to thebase plate 20 by means of the circular nut 35 which occupies acounterbore within the base plate 28. A worm 36 meshes with the wormwheel 32 and its shaft 3? journals d in a housing 38 which is hinged onthe pin 39. The housing 38 is urged toward a stop 48 by means of aspring 4!. The shaft 3'! is manually rotated by means of a knurled head42.

Keyed near the upper end of the main spindle 23 is the gun arm azimuthplate 43 which is retatable within the dial wheel "it which is mountedon the sleeve 34 and integral therewith. The dial wheel 44 has formedthereon the gun arm azimuth setting scale 45 and a target arm azimuthscale 46. The plate 33 has secured thereto a Vernier 41 by means ofwhich mills and fractions thereof in tenths may be read on the scale 45.

Fixed to the hub 33 is an observation point to aiming point arm 48,which will be referred to as the O. A. arm. The arm 48 is provided witha Vernier 49 by means of which readings in mills and tenths thereof maybe made on the aiming point azimuth scale 46. Secured to the outer sideof the dial wheel 44 is the observation point to target arm 50, whichwill be referred to as the O. T. arm.

Secured on the upper end of the spindle 23 is the observation point gunarm 5! which is circular in cross section having a scale 52 which isgraduated to read in yards. On the arm 5! is a slide 53 which isprevented from rotating on the arm 51 by the screw point 54 whichoccupies a V groove 55 in the side of the arm 5i. The point 54 is formedon the end of a screw having a knurled head 56. To the slide 53 isattached a Vernier 5'! by means of which fractional readings may be madeon the scale 52.

The O. A. arm 48 is right angular in cross section and is provided witha scale 58 which is graduated to read in yards. On the arm 48 is mounteda slide 59 which carries a pinion Bil which meshes with a rack 6! formedon the lower side of the arm 58. A knurled head 62 is utilized to rotatethe pinion 65 for the purpose of moving the slide 59 along the arm 48. AVernier 53 is attached to the slide 59 and operates in conjunction withthe scale 58.

Extending vertically from the slide 59 is a pivot cs upon which ismounted a slide 65 which receives the gun aiming point range arm 65which will hereafter be referred to as a G. A. arm. The arm 66 is alsoof a right angle cross section and is free to move in the slide 65 whennot held by the knurled screw 57, which is threaded into the slide 55and presses against the vertical leg of the arm 65. The G. A. arm 56 isprovided with a G. A. scale 68 which is graduated to read in yards. Theslide 65 is provided with a Vernier 69 which operates in conjunctionwith the G. A. scale $8.

On the inner end of the G. A. arm 66 is disposed a circular plate it?within which is rotatably mounted on the pivot H a disk l2. To the diski2 is attached a gun target range arm 2'3 which will be referred to asthe G. T. arm. A scale it in mills is formed on the plate l8, and thedisk l2 carries a Vernier 715 which operates in conjunction with thescale i l.

The O. T. arm 56 is right angular in cross section, as is the G. T. arml3, and these two arms are pivotally and adjustably connected to eachother in a manner identical with that described for the arms 18 and 66.In this case the slide I6 is moved along the O. T. arm Ed by means of aknurled screw ill, and the slide E8 is clamped to the G. T. arm 73 bymeans of the knurled screw T9. The slides l6 and i8 pivot on the pinBil.

The slide it is provided with a Vernier 8! by means of which settingsmay be made on the yard scale 82 on the O. T. arm 56. The slide 18 isprovided with a Vernier 83 by means of which readings may be taken fromthe yard scale B l on the G. T. arm l3.

It is desirable to provide a cover plate 85 on the under side of thebase plate 20 and a cover plate 86 on the top side thereof through whichthe hub 33 projects and is free to rotate.

In order to give a clearer understanding of the operation of thisinstrument four positions are shown, namely the observation point whichwill be referred to as O, the target T, the aiming point A and the gunG.

The distance between the observation point and gun position isestablished by means of a range finder or actual measurement, and thepivot l l, which corresponds with the gun position on the instrument, ismoved to a corresponding position on the arm 5| which, in the exampleshown in Fig. 2, will be 7.31.

The distance from the observation point 0 to the aiming point A islikewise determined by a range finder and is set upon the scale 53 ofthe arm 48 by means of the Vernier 63, the necessary movement beingsupplied by the rotation of the knurled head 52. This distance is 17.65.

The distance from the observation point 0 to the target T is thendetermined by means of a range finder and the setting of the pin Bilalong the scale 82 is made by the rotation of the knurled screw T1, inthis instance the setting being 14.1.

It is also necessary to set off the angle in mills between the target Tand the aiming point A with the observation point 0 as a vertex. Thissetting may be at the Vernier 49.

The final setting is the angle between the target T and the gun G withthe observation 0 as a vertex.

The order of making the settings is of small importance and the valuesgiven are only for a representative example.

In this instrument the unit of angular measurement employed is that ofthe mill in which the circle is divided into six thousand four hundredparts and the scales A5 and A6 are correspondingly graduated, theverniers 41 and 49 making it possible to read accurately to one mill. Inthe example shown in Fig. 2 the Vernier l'l is set at 24 hundred mills,which is the angle T. O. G. which, in this instance, has beenestablished as twenty-four hundred mills, while the angle T. O. A. hasbeen established as sixteen hundred mills, and is set at the Vernier 49.

Two unknown quantities which are of importance and which it is desiredto determine are the angle T. G. A., which is the firing angle, and alsothe distance T. G., which is the range in yards between the gun and thetarget.

The various arms having been set as described it follows that there havebeen constructed on the instrument two triangles which are proportionalto the triangles O. T. G. and O. A. G., and since the triangles aresimilar their elements must also be proportional. Therefore it is clearthat the reading on the Vernier 15 which, in this instance, is fourteenhundred and sixty-seven mills, must be the firing angle between the baseline G. A. and the firing line G. T. Also the range, or the distance G.T., may be read directly from the Vernier 83 which, in this. case, isnineteen hundred and ninety-seven yards.

The setting on the arm 66 can be read on the Vernier 59. In thisinstance, the reading being 13.5. It must be understood that thisreading while not essential to the solving of the problem, may be usedas a check on the other readings and settings.

Therefore it can be seen that all of the sides of the triangles aredirectly readable from the arms and all of the angles may be readdirectly or computed indirectly.

To those familiar with the common forms of artillery problems it is wellunderstood that there is usually employed an observation point 0 fromwhich must be visible the target, the aiming point and the gun position.It is vital that the aiming point be visible from the gun position, butit is neither necessary or desirable that the target be visible from thegun position.

What actually transpires when this instrument is used is that when a gunis placed in position and an aiming point and observation point selectedfor that position, there is at once established a base of angularmeasurement, namely the line 0. A. The length of the line 0. A. must ofcourse be determined by any convenient method, as well as the distance0. G. between the gun and the observation point.

When these distances and angular measurements are once established andcorresponding settings made thereon at the instrument the only factorwhich alters the problem is the change in the position of the target T.For any new position of the target for a given setting of theobservation point, gun and aiming point, no other adjustment need bemade at the instrument other than to set the pin 8! at a distance alongthe arm 5!] to correspond with the length of the line 0. T., and to movethe arm 58 to the new angle T. O. G.

While in the position shown in the diagram in Fig. 3 the various arms onthe instrument are parallel to the various lines in the problem, this isof course unnecessary as the orientation of the instrument has nobearing upon the solution of the triangles. In other words, for a givengun setting and target position, as well as observation and aimingpoints, certain of the values are findable by means of existinginstruments such as range finders and angle measuring instruments. Theseestablished lines are then registered on the corresponding lower armsand dials of the instrument, which causes these arms to assume definiterelative positions resulting thereby in the mechanical determination ofthe unknown factors in the problem without resorting to the use ofmathematics, charts or other instruments other than those referred to.

It can be seen from the foregoing that maximum degrees of speed andaccuracy are thereby attainable, and since these two elements are ofmajor importance in the control of artillery fire it can be seen thatnot only is it possible to effect material savings in ammunition and gunlife in the finding of a target, but also of greater importance is thefact that the target can be struck at the earliest possible moment.

We claim:

1. An instrument for solving problems in artillery fire controlcomprising adjustable members for simulating two triangles having acommon base, one vertex at an end of said base having a pivot joint, theremaining vertexes having slidable pivot joints and means for settingand reading the angles of said triangles and for setting and reading thelengths of the sides thereof.

2. An instrument for solving problems in artillery fire control havingin combination adjustable members for simulating a pair of triangleshaving a common base, the angles and lengths of the sides of saidtriangles being adjustable, each of the sides of the said trianglesbeing pivotally connected at each end to an adjacent side, certain ofsaid pivotal connections being slidable and scales associated with saidtriangles for reading the values thereof in angular and linealmeasurements.

3. The instrument described in claim 2, together with means forestablishing the length of the base of both triangles, the length of theadjacent sides extending from the base and the length of onehypothenuse, together with means for establishing the angle includedbetween said base and one of said established sides, as well as theangle between said base and said hypothenuse.

4. The instrument described in claim 2 in which the base of the triangleconsists of a graduated arm along the length of which is adjustably andpivotally mounted a gun arm protractor having a gun target range arm anda gun aiming point range arm, a double protractor pivotally mounted atthe opposite end of said gun arm including a gun arm azimuth scale and atarget arm azimuth scale, an observation point target arm radiating fromthe center of said double protractor and secured thereto and having apivotal connection to said gun target range arm, said connection beingslidable with relation to both said gun target range arm and observationpoint target arm, and an observation point aiming point arm pivotallymounted on the center of said double protractor and having a Vernierreading on one of the scales thereof, and a pivotal connection slidablyattached to each of said gun aiming point arm and said observation pointand aiming point arm.

5. An instrument of the class described having in combination a head, avertical spindle mounted on said head, a base plate supported by saidspindle, a sleeve supported by said base plate in alignment with saidfirst mentioned spindle, a gun arm azimuth plate secured near the upperend of said sleeve, a graduated observation point gun arm secured at theupper end of said sleeve,

a pivot slidably mounted on said arm, a plate rotatably mounted on saidpivot, a disk also mounted on said pivot, a Vernier and scale carried bysaid plate and disk, a gun target arm mounted on said disk, a gun aimingpoint arm secured to said plate, a dial wheel surrounding said ELLIS C.LYONS. RAYMOND Gr. MCMAHON.

